Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full behavioral burden. It only states the calculation and lists inputs; it does not disclose whether the operation is pure, deterministic, requires authentication, or has any side effects, rate limits, or error behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences with zero filler. The purpose is front-loaded and the input summary is compact and directly useful, making the definition easy to scan.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be described. However, with no annotations, 0% schema coverage, and an unexplained api_key parameter, the definition is only minimally complete for correct invocation; array alignment and authentication expectations remain ambiguous.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate fully. It names four required inputs in natural language but omits the api_key parameter and gives no detail on array structure, ordering correspondence between mw_reactants and equivalents, units for MW values, or equivalent definitions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: 'Calculate reactant masses needed for a target product mass.' This clearly identifies a stoichiometry calculation, though it does not distinguish itself from other covabasic tools such as covabasic_equation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides no when-to-use guidance, prerequisites, or alternatives. The description implies a calculation context but does not tell the agent when this tool is preferable to closely named siblings or what conditions are required.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.